38 Special 2400 Loads

[Taco Belly]

Hello all,

I am contemplating picking up a Marlin Cowboy in 38 Special only, and would like to know if anyone here has some chrono data on 158-160 Cast with 2400 (10-11.5 gr or so) out of a carbine.

I would normally only shoot standard 38 loads, but would like to know what 2400 loads could do in a rifle. Thanks.

Jeff

[rintinglen]

158 grn RN (358-311) did 1170 out of a 20 inch Rossi with 9.2 grains of 2400.
The marlin is a good strong gun that could probably easily stand the loads you are talking about, but these days I have qualms about such doings. I have gone higher, but I don't recommend it if you have a bunch of snubbies like me that most likely would take it unkindly if I were to mix one of thse in with the regular 4.0 grain 231 loads. 5.0 grains of Unique works better, but there are literally thousands of good 38 loads.

[geargnasher]

Use Unique or Universal. You're trying to balance good low-pressure burn characteristics with as slow a powder as you can reasonably get for your gun. 2400 is nasty, cruddy stuff at any pressure, MUCH worse at safe .38 Special pressures. You don't want all those tiny unburned granules getting in your action and mucking things up. The new Unique will burn fairly cleanly at .38 pressures and still utilize your barrel length better than the typical .38 powders like Bullseye and Clays.

Gear

[maglvr]

"I would normally only shoot standard 38 loads, but would like to know what 2400 loads could do in a rifle. Thanks."


You would be amazed!
It's not real hard to get a 38spl casing to push the 173gr 358429/2400 combo over 1300fps in a revolver, I do it all the time. Naturally in my Marlin 1894C it goes a LOT faster yet, 1600+ fps. (IIRC)!
A fun and serious little round!!
I also use the same charge under the CP 160gr. WFN. No gas checks for me.

358429
---------
13.5gr./2400
--------
SPP

[garym1a2]

Here is what I got with a 158swc gas check boolit in my Rossi 20 inch.
5.4 grain unique, 1260fps ave
5.8 unique 1320 average
10.0 grains of 2400, 1390 fps average.

With the 357 case I get 14.9grain and 1720fps average.

Above loads are the 158 lee swc-gc. With the small Lee 105swc and 3.4 Bullseye I get 1050 to 1100fps.
With a 158 lead rnd nose and 3.4 bullseye I get about 1020 fps.


Hello all,

I am contemplating picking up a Marlin Cowboy in 38 Special only, and would like to know if anyone here has some chrono data on 158-160 Cast with 2400 (10-11.5 gr or so) out of a carbine.

I would normally only shoot standard 38 loads, but would like to know what 2400 loads could do in a rifle. Thanks.

Jeff

[hes]

I use 10 grains 2400 with 358156GC and 4.3 grains 231 with 125 cast.

[NHlever]

I use 10 grains 2400 with 358156GC and 4.3 grains 231 with 125 cast.

That is the load I used in the old, and more simple days of my youth in a K-38 with a 6" barrel. I harvested everything legal to hunt in NH except a bear with that load behind the then new Speer 146 grain HJHP. My small game load was a 148 wadcutter over the standard load of 2.7 grains of Bullseye, and I remember getting my limit of grouse one day with that combo. These days I might use the Lee 158 RNFP, but all my rifles are .357 right now as are my handguns in .35 caliber. They can make more noise than a .38 Special, but sometimes I sure wish for the shorter chamber of the .38 for every day loads.

[Larry Gibson]

Couple days ago I ran a test of Alliant 2400 in the 38 SPL under a 358477 bullet of 150 gr. Loads ranged from 8 gr to 13.5 gr (100% loading density). I used 10 shot strings measuring the velocity and pressure with the Oehler m43. Test gun was a Contender with 7.94" barrel. Cases were R-P, primers WSPs, alloy was WWs +2% tin sized at .360 and lubed with Javelina. The bullets were seated to an OAL of 1.485 (crimp groove) and a heavy roll crimp applied.

All the loads from 8 to 12.5 gr exhibited "reasonable" accuracy (would have been ok if a revolver but was pretty poor for this Contenderwith a 2.5X scope). The ES for each of those loads was very poor ranging from just over 100 fps to 345 fps with the 10 gr load. There were 2-3 very low inconsistent velocities in each test string from 8 to 12.5 gr of 2400. A heavier bullet would probably help with ignition consistency. The ES of the psi also varied to excess. The 11 gr load MAP was 20,300 psi(M43) which is max for .38 +P loads. Problem was that is an average psi and 4 shots exceeded that psi with one shot at 25,000 psi(m43). That is definately into .357 Magnum psi range.

The 2400 did not start to burn consistently under this bullet until 13 gr was reached. At 13 gr the MAP was 27,100 psi(M43) which is more than several factory .357 loads I've measured. The 13.5 load produced a MAP of 28,100 psi(M43) with an excellent ES of only 200 psi. The velocity was 1516 fps. Years ago I used that very load under the 358156 in 38 SPL cases in a Colt Trooper (service revolver with OSP) and a Ruger BH with excellent accuracy.

I would say that 9.5 gr 2400 under a 150 gr cast bullet is about max for standard .38 SPL loads. However the inconsistent ignition would lead me to a more suitable powder. However in the 357 using 2400 under 150 170 gr cast bullets has proven it's worth there.

FYI; the following 357 Magnum factory loads were also tested when the .38 SPLs were tested in the same Contender barrel;

Win 125 JHP; 28,200 psi
Rem 158 LSWC; 25,100 psi
Rem 110 JHP; 24,400 psi
Federal 158 LSWC; 28,500 psi
S&W 158 LSWC; 29,200 psi
Win 158 LSWC Lubaloy; 30,200 psi
Federal 110 JHP; 23,400 psi

Larry Gibson